The Rise of Mass Timber: How Wood is Making a Comeback in Modern Structures

Mass timber construction is revolutionising the UK building sector with engineered wood products offering sustainable alternatives to traditional materials. Cross-laminated timber (CLT) and other advanced wood technologies are not only addressing the country’s housing crisis but are proving essential to meeting ambitious net zero carbon targets by 2050.

Key Takeaways

Mass timber buildings store carbon rather than emit it, with each cubic metre saving approximately 2 tonnes of CO2 compared to conventional materials
The UK government’s Timber in Construction Roadmap 2025 aims to increase domestic timber use and reduce the 80% reliance on imports
London’s Hackney borough has emerged as the unofficial capital for mass timber with 48 documented CLT projects
Mass timber construction offers faster build times despite initially higher costs and insurance premiums
Current UK regulations use a performance-based approach to timber building safety rather than prescriptive height restrictions

The Environmental Impact of Mass Timber

The environmental benefits of mass timber construction are substantial and well-documented. Timber-framed houses demonstrate reduced embodied carbon of 1.7-3.2 tonnes of CO2 equivalent compared to similar masonry buildings. This stark difference becomes even more significant when looking at larger structures, where cross-laminated timber emits 75% less carbon dioxide than reinforced concrete.

Wood’s carbon storage potential is remarkable. The UK currently stores 400 million tonnes of CO2 in Harvested Wood Products, with each cubic metre of wood containing approximately 0.9 tonnes of stored carbon. When timber replaces carbon-intensive materials like steel or concrete, each cubic metre saves about 2 tonnes of CO2 from entering the atmosphere.

Construction timber already contributes significantly to the UK’s carbon reduction efforts:

Over 1 million tonnes of additional CO2 stored annually in new timber homes
Potential to increase to 3 million tonnes of CO2 storage per year by 2050
20% reduction in embodied emissions when using timber frame instead of masonry
Up to 60% reduction possible with more extensive timber substitutions

As the UK works toward its net zero construction goals, these carbon benefits make timber an increasingly attractive option for developers and policymakers alike.

Pioneering UK Mass Timber Projects

The United Kingdom has emerged as a global leader in mass timber construction, with over 100 completed CLT projects documented between 2005-2018. London has been at the forefront of this movement, hosting some of the world’s most innovative timber structures.

Murray Grove in London, completed in 2009 by Waugh Thistleton Architects, made history as the world’s first nine-storey residential timber tower. This groundbreaking project demonstrated that mass timber could successfully replace traditional materials in multi-storey buildings, opening new possibilities for sustainable urban construction.

Following this success, Dalston Works (2017) pushed boundaries further by using 3,852 cubic metres of CLT—more mass timber by volume than any building of its time. This impressive structure stores approximately 9,000 tonnes of carbon dioxide, making it effectively carbon negative over its lifetime by storing double the emissions produced during construction.

The UK’s tallest CLT building currently stands at 17-21 Wenlock Road in Hackney, a 10-storey hybrid structure that combines steel and timber elements. This innovative approach enables complex architectural forms while maintaining sustainability benefits, showcasing how different structural systems can work together effectively.

Government Support for Timber Construction

The UK government has made significant strides in promoting timber construction through its Timber in Construction Roadmap 2025, launched in February 2024 by Environment Minister Mary Creagh. This comprehensive strategy aims to increase England’s tree canopy from the current 14.5% to 16.5% by 2050, while simultaneously boosting domestic timber production.

Currently, 80% of timber used in UK construction is imported, representing a substantial opportunity for domestic growth and job creation. The government has committed to building 1.5 million homes over the current Parliament using Modern Methods of Construction, with timber playing a central role.

The roadmap identifies seven priority areas:

Improving data on timber use and whole life carbon assessment
Promoting safe and sustainable timber as a construction material
Increasing skills and capacity across the supply chain
Addressing fire safety concerns to safely expand mass timber use
Streamlining regulatory processes for woodland creation
Reviewing timber procurement policies to support domestic producers
Supporting research in wood modification and hybrid timber systems

The government has also committed to reviewing the Timber Procurement Policy in 2025, with potential inclusion of British timber certifications in approved sustainability standards—a move that would significantly support domestic producers.

Regional Leadership in Mass Timber Adoption

The London Borough of Hackney has emerged as the UK’s unofficial capital for mass timber construction, hosting 48 case study projects within Greater London’s portfolio of documented CLT buildings. This concentration reflects Hackney Council’s forward-thinking approach to sustainability, with the borough nearly implementing a ‘Timber First’ policy in 2012 that would have required planning applications to demonstrate consideration of timber solutions.

Hackney’s leadership extends beyond policy to practical implementation, with local officials noting the borough’s pride in pioneering tall timber buildings and encouraging wider adoption of engineered timber. This local government support has created a visible cluster of successful projects that serves as inspiration for developers and architects throughout the UK.

The stark regional disparities in timber construction across the UK highlight the impact of local leadership and policy. While only 9% of English new build homes were timber framed in 2019, Scotland achieved an impressive 92% adoption rate. This contrast demonstrates the significant potential for growth in England if supportive policies and knowledge sharing can be implemented more widely.

Local councils are increasingly recognising that planning guidance should promote sustainably sourced wood as a primary construction material for both new-build and refurbishment projects where feasible, aligning with the National Planning Policy Framework’s focus on sustainable development.

Economic Considerations of Mass Timber

The economics of mass timber construction present a nuanced picture of costs and benefits. Mass timber buildings typically cost 3-6% more than conventional concrete and steel structures during the construction phase. This initial premium is partially driven by material costs and partly by the current scale of the industry.

Insurance represents another significant cost factor, with premiums for timber buildings running 25-40% higher than traditional construction. These higher rates reflect both perceived and actual risks related to fire safety and moisture damage, though industry initiatives are working to address these concerns through specialized insurance facilities and risk pooling.

Despite these challenges, mass timber offers compelling economic advantages:

Dramatically reduced construction times with erection speeds of 340 to 4,780 square feet per day
Lighter foundations due to timber’s reduced weight compared to concrete
Decreased on-site labour requirements through precision off-site manufacturing
Potential for simpler logistics in urban settings
Long-term value through superior energy efficiency and reduced carbon footprints

The British employment landscape in timber processing includes approximately 7,200 full-time positions in primary wood processing as of 2023. The sawmilling sector specifically employed 7,472 people in 2024, with businesses averaging 15.7 employees—indicating a specialised but fragmented industry structure with growth potential as domestic demand increases.

Fire Safety and Regulatory Framework

The UK employs a performance-based approach to building regulations rather than prescriptive restrictions, which has enabled the diverse range of CLT buildings across the country. Unlike jurisdictions that specify maximum heights for combustible materials, UK regulations require design teams to demonstrate performance compliance, allowing for innovation within safety parameters.

Following the Grenfell Tower tragedy, the government introduced significant restrictions on combustible materials in building exteriors. New regulations require timber wall systems to pass large-scale fire safety tests before use on residential buildings between 11 and 18 metres tall. This represents a more nuanced approach than blanket bans while ensuring appropriate fire safety measures.

In practical terms, CLT elements in multi-storey buildings typically require complete coverage with fire-retardant dry-lining to achieve 90-minute structural integrity during fire conditions. Industry experts emphasise that solid timber panels demonstrate predictable charring behaviour, with panels 100-150mm thick providing reliable fire performance when properly specified.

This regulatory framework has supported the UK’s position as a leader in safe mass timber construction while maintaining rigorous safety standards. The evolution of building regulations continues to shape how innovative construction methods are implemented, with ongoing research informing future standards.

Future Prospects and Challenges

The UK mass timber sector faces several critical challenges that require coordinated industry response. Insurance costs represent a major barrier, with premiums significantly higher than for conventional construction. However, the industry is developing solutions including the Mass Timber Construction Insurance Facility and exploration of alternative risk transfer mechanisms.

Skills development across the supply chain remains essential, with recommendations for engagement with professional bodies including RIBA and IStructE to upskill architects and structural engineers. The industry also requires development of dedicated standards and regulations to support safe use of mass timber in all building types, including those taller than 18 metres.

Despite these challenges, the future looks promising for mass timber in the UK. The global CLT market is projected to reach £2.8 billion by 2030, with European demand including the UK driving significant growth. The Climate Change Committee has recommended that government develop new policies to increase wood use in construction, recognising timber’s essential role in tackling built environment emissions.

Ongoing research and development in several areas will further enhance timber’s construction potential:

Advanced wood modification techniques to improve durability and performance
Development of improved adhesives with lower environmental impact
Hybrid timber systems combining wood with complementary materials
Digital design and manufacturing processes to optimise material use
Fire performance improvements through innovative treatments and designs

The increasing preference for renewable materials in construction, combined with stronger policy support and emerging regulations, positions mass timber as a preferred choice for sustainable urban construction aligned with broader environmental goals and national zero-carbon ambitions.